If an item is not as described, or all items are not included in the package as promised, you should contact the Seller immediately. Put into writing (email) exactly what is wrong or missing, versus what was described in the ad. After an email is sent, you should attempt to reach the Seller by telephone. Communicating about problems by voice vs. email is a much more effective means of eliminating misunderstandings and reaching a resolution.
If you are unable to reach an agreement with the Seller, you may consider leaving a "Neutral" or "Negative" feedback for that member. If you are seriously concerned about the problem, you should file a "Dispute" with Audiogon in lieu of leaving feedback. This is a somewhat formalized process which allows a neutral evaluation of the problem: Submit a Transaction Dispute.